Microscopic Theory of Fluctuating Hydrodynamics in Nonlinear Lattices

Journal Article · 02 July 2021 · Physical Review Letters

DOI: https://doi.org/10.1103/physrevlett.127.010601 · OSTI ID:1849388

Saito, Keiji  ^[1]; Hongo, Masaru  ^[2]; Dhar, Abhishek ^[3]; Sasa, Shin-ichi  ^[4]

---

1. Keio University, Yokohama (Japan); OSTI
2. Univ. of Illinois, Chicago, IL (United States); Inst. of Physical and Chemical Research (RIKEN), Wako (Japan)
3. Tata Inst. of Fundamental Research, Bengaluru (India)
4. Kyoto Univ. (Japan)

The theory of fluctuating hydrodynamics has been an important tool for analyzing macroscopic behavior in nonlinear lattices. However, despite its practical success, its microscopic derivation is still incomplete. In this work, we provide the microscopic derivation of fluctuating hydrodynamics, using the coarse-graining and projection technique; the equivalence of ensembles turns out to be critical. The Green-Kubo (GK)-like formula for the bare transport coefficients are presented in a numerically computable form. Our numerical simulations show that the bare transport coefficients exist for a sufficiently large but finite coarse-graining length in the infinite lattice within the framework of the GK-like formula. Finally, this demonstrates that the bare transport coefficients uniquely exist for each physical system.

• Research Organization: Univ. of Illinois at Urbana-Champaign, IL (United States)
• Sponsoring Organization: KAKENHI; USDOE Office of Science (SC), Nuclear Physics (NP)
• Grant/Contract Number: FG02-01ER41195
• OSTI ID: 1849388
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 1 Vol. 127; ISSN 0031-9007
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English